Major Yuri Alexeyevitch Gagarin, the world's first astronaut, was last night undergoing a rigorous medical examination to find out the effects on him of his journey yesterday in orbit round the world in the Soviet space ship Vostok.

"The Columbus of interplanetary space," as Moscow Radio described him, is expected to reach Moscow tomorrow where a hero's welcome is being prepared for him. Major Gagarin, aged 27, a member of the Red Air Force, is a married man with two young daughters.

Early yesterday morning his space ship, weighing more than four and a half tons without its last-stage rocket, went into orbit at 18,000 m.p.h., made rather more than one complete circuit of the earth, and landed safely at a prearranged area 108 minutes later. The Russian places where he left and landed were not disclosed.

Mr Khrushchev, according to Tass, told him by telephone: "You have brought glory to our homeland. You have shown courage and heroism. You have made yourself immortal ... I shall be glad to meet you in Moscow. I, togethe r with you and all our people, will solemnly celebrate this great feat." The Major reported he was "well, with no injuries".

Meanwhile in Moscow, to martial music broadcast by loudspeakers, crowds were filling the streets, some singing and chanting "To the cosmos," in a burst of enthusiasm that was said to have been the greatest seen in the capital for many years.

US praises the Soviet feat

Mr Macmillan and President Kennedy yesterday led the world in hailing Russia's success. In Ottawa, the British Premier described the orbiting as "a very notable achievement", and added that he was sending a message of congratulations to Mr Khrushchev.

President Kennedy told a press conference that the flight was "a most impressive scientific accomplishment."

He had sent a message to Mr Khrushchev, saying: "The people of the US share with the people of the Soviet Union their satisfaction for the safe flight of the astronaut in man's first venture into space ... It is my sincere desire that in the continuing quest for knowledge of outer space our nations can work together to obtain the greatest benefit to mankind."

He said of the relative positions of the US and Russia in space exploration that there was no doubt that "we are behind". But the latest Soviet feat did not mean the free world was losing the world contest with communism.

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